Excerpted from a biotech newsletter:

Tysabri (natalizumab) is a breakthrough. Never before was a drug developed that made it difficult for the immune system cells to mobilize and stage an autoimmune attack. The hypothesis was validated time and time again with the confirmed unparalleled efficacy of Tysabri. Data from the market and from testing continue to demonstrate the drug’s superior efficacy in containing most MS symptoms. In the AAN meeting Elan and
Biogen Idec presented study results demonstrating that Tysabri sustains visual function, diminishes disability, boosts overall quality of life (QoL), cognition and fatigue in multiple sclerosis (MS) patients. Tysabri is described as changing the way neurologists and patients define success in the treatment of MS.

Here are some of the drug’s findings as presented in the AAN meeting :

- Sustaining visual function and improving vision;
- Sustaining physical function and mental improvement;
- Improving psychological wellbeing;
- Reducing fatigue; and improving cognitive function.

Loss of vision and difficulty walking are among the most concerning symptoms associated with MS. Psychological disturbances are also devastating to patients and families.

The PML Problem and the PML expected test
Here we have good news that we hope will end the fear campaigns against Tysabri.

Perpetrating frightening news for personal gain hurts the firm’s stock price, the companies, their employees, the great science, and more important, the patients who believe all they read on the Internet. Such rumors have caused patients who badly need the drug to refuse to take it. At the AAN meeting, Elan and Biogen Idec announced that they have evidence that patients who developed progressive multifocal leukoencephalopathy (PML) had antibodies to JC virus that causes PML prior to using Tysabri. The patients’ blood, which was collected long before they received Tysabri, tested positive for the virus. In light of these findings, scientists are now optimistic that a test that pinpoints those vulnerable to developing PML is possible.

I have changed some of the wording to make the points more clear. I do not have a link yet since it is a pay site and it takes a few days for it to be public but this is the gist of the newsletter's take on Tysabri and the assay for PML. I will post a link as soon as one becomes available.